Two clinically applied preservation methods for organs are known: (1) initial perfusion for about 5 min with subsequent cold storage (2.degree. C.), and (2) continuous perfusion using solutions containing albumin or plasma.
Many of the solutions used for initial perfusion with subsequent cold storage are based on the solutions of Collins et al. (1969) Lancet 2:1219 and Sacks et al. (1973) Lancet 1:1024. Ross et al. (1976) Transplantation 21:498 compared canine renal preservation following flushing and storage for 72 hours in various solutions. It was found that only kidneys preserved in a hypertonic citrate (HC) solution (comprising in part 80 mM K.sup.+, 55 mM citrate, 400 mOsmol/kg, pH 7.1) survived after 72 hours. The Collins and Sacks solutions in part contained 115-126 mM K.sup.+, 290-430 mOsmol/kg, pH 7.0-7.3. Wall et al. (1977) Transplantation 23:210 reports the hypothermic preservation of human livers for up to about 4 hours in a solution in part comprising 250 mg dextrose, and 15 mEq potassium phosphate. Bishop & Ross (1978) Transplantation 25:235 reported that renal function was preserved best in the HC solution of Ross et al. (1976) supra, rather than other available solutions. Fischer et al. (1985) Transplantation 39:122 found a new preservation solution for hypothermic ischemic storage (comprising in part 110 mM Na.sup.+, 115 mM K.sup.+, 400 mOsm/kg, solvent D.sub.2 O, 110 mM HEPES) to be superior to other solutions in clinical use, including Collins, Sacks, and HC.
Among the solutions used for continuous organ perfusion, Belzer et al. (1985) Transplantation 39:118 reported a newly developed solution which preserved renal function when kidneys were perfused for 48 hours and stored for 24 hours (comprising in part 80 mM sodium gluconate, 22 mEq/l K.sup.+, 128 mEq/l Na.sup.+, 4.9 mM adenosine, 10 mM HEPES, 3.0 mM glutathione, 3.75 g % albumin, pH 7.45). Kallerhoff et al. (1985) Transplantation 39:485 examined the effect of temperature on pH of organs continuously perfused with two different solutions (Euro-Collins: 10 mM Na.sup.+, 115 mM K.sup.+, 198 mM glucose, 406 mOsm/L, pH 7.2 at 20.degree. C.; HTK: 15 mM Na.sup.+, 10 mM K.sup.+, 2.0 mM tryptophan, 180 mM histidine, 30 mM mannitol, 310 mOsm/L, pH 7.3 at 8.degree. C.). At incubation temperatures between 5.degree. C.-35.degree. C., HTK solution maintained pH at consistently higher values than Euro-Collins solution.
Klebanoff & Phillips (1969) Cryobiology 6:121 describe hypothermic asanguinous perfusion of dogs perfused with buffered Ringer's lactate at 7.1 to 16.degree. C. Segall et al. (U.S. Pat. No. 4,923,442) describe a blood substitute capable of maintaining a subject and its organs at temperatures below 20.degree. C. having four different solutions--a base solution, a cardioplegia-inducing solution, a cardioplegia-maintaining solution, and a recovery solution. The base solution contains electrolytes in physiological concentration, a macromolecular oncotic agent, a conventional biological buffer effective at physiological pH, sugar, and K.sup.+ ranging from 4-5 mEq. The cardioplegia-inducing solution had a K.sup.+ concentration of 25-45 mEq; the cardioplegia-maintenance solution had a K.sup.+ concentration of 15-45 mEq; and the recovery solution had a K.sup.+ concentration of 6-10 mEq. Segall et al. (U.S. Pat. No. 5,130,230) further described the four-solution system, where the recovery solution contains 0-10 mEq K.sup.+.